The present invention relates to land-based combustion turbines used for generating electric power and for other industrial purposes and more particularly, to combustor baskets employed therein.
In general terms, the typical prior art combustion turbine comprises three sections: a compressor section, a combustor section, and a turbine section. Air drawn into the compressor section is compressed, increasing its temperature and density. The compressed air from the compressor section flows through the combustor section where the temperature of the air mass is further increased. From the combustor section the hot pressurized gases flow into the turbine section where the energy of the expanding gases is transformed into rotational motion of a turbine rotor.
A typical combustor section comprises a plurality of combustor baskets arranged in an annular array about the circumference of the combustion turbine. In conventional combustor technology pressurized gases flowing from a compressor section are heated by a diffusion flame in the combustor basket before passing to the turbine section. In the diffusion flame technique, fuel is sprayed into the upstream end of the combustor by a nozzle. Combustion occurs in a primary combustion zone downstream of the nozzle. Incomplete combustion, caused by incomplete mixing of the fuel and compressed air, results in the production of smoke and other undesirable pollutants.
Increasing environmental awareness has resulted in more stringent emission standards for combustion turbines. Voluntary efforts to improve combustion turbines as well as mandatory requirements of compliance with emission standards have made it desirable to develop combustion turbines which generate more power more efficiently with less environmental impact. To this end, it has been desirable to design an improved combustor capable of heating compressed gases to increased temperature levels while producing reduced levels of smoke.